The title had me captivated. However:

This post could use some more exposition in between the quotes. When "parasite load" was mentioned, my immediate assumption was that this was a metaphorical usage referring to "parasitic" ideas or memes, and was quite confused when I encountered a discussion of skin infections and whatnot, suggesting that somehow the literal sense of biological parasites was intended. This was confusing because I wasn't expecting any connection between psychological personality traits such as openness on the one hand and susceptibility to infectious disease on the other. Maybe such a connection is well-known in some circles, but I was totally unprepared for it and it came across to me as a bizarrely privileged hypothesis. Some more emphatic exposition, saying in effect "yes reader, I really do intend to relate the personality trait of openness to the medical phenomenon of infectious diseases" would have been helpful.